﻿#define _CRT_SECURE_NO_WARNINGS 1

//编程初学者入门训练第二十四题
//BC26 计算三角形的周长和面积
//https://www.nowcoder.com/practice/109a44d649a142d483314e8a57e2c710?tpId=107&tqId=33307&rp=1&ru=/exam/oj/ta&qru=/exam/oj/ta&sourceUrl=%2Fexam%2Foj%2Fta%3FtpId%3D107&difficulty=undefined&judgeStatus=undefined&tags=&title=

#include <stdio.h>
#include <math.h>

int main() {
    int a = 0;
    int b = 0;
    int c = 0;
    scanf("%d %d %d", &a, &b, &c);
    double circumference = a + b + c;
    double area = 1 / 4.0 * sqrt((a + b + c) * (a + b - c) * (a + c - b) * (b + c - a));

    printf("circumference=%.2lf area=%.2lf", circumference, area);
    return 0;
}
